Leading lights

For the racehorse, see Leading Light.
Nantucket Harbor Range Lights[1] The dayboards are type KRW, see below.
A pair of leading lights in Bremerhaven, Germany, with the rear light in a proper lighthouse and the front light on a smaller tower. No standardised markings are used here.

Leading lights, also known as range lights in the United States, are a pair of light beacons used in navigation[2] to indicate a safe passage for vessels entering a shallow or dangerous channel; they may also be used for position fixing. At night, the lights are a form of leading line that can be used for safe navigation. The beacons consist of two lights that are separated in distance and elevation, so that when they are aligned, with one above the other, they provide a bearing. Range lights are often illuminated day and night.

In some cases the two beacons are unlighted, in which case they are known as a range in the United States or a transit in the UK. The beacons may be artificial or natural.

  1. ^ Light List, Volume I, Atlantic Coast, St. Croix River, Maine to Shrewsbury River, New Jersey (PDF). Light List. United States Coast Guard. 2009. p. 135.
  2. ^ "Dictionary of the International Association of Lighthouse Authorities". International Association of Lighthouse Authorities.